Improved slate-cdttek



@niet ma geen ffm,

THOMAS R. DRUMMON D, OF HARTFORD, CONNECTICUT.

Letters .Patent No. 67,963, dated August 20, 1867-.

Inurnovnn stars-corren.

'ro ALL WHoM rr MAY eo'NenRN;

B it known that I, THOMAS R. DRUMMOND, of Hartford, in the eountyof Hartford, and State of Con- -necticut, have invented a. new and improved Slate-Cutterg and I do hereby declare that the following is a full, clear, and exact description thereof, which willenable others skilled in the art to make and use the same, reference being had to the accompanying drawings, forming part of this specification.

This invention relates toa new and improved method .of cutting slate; and the invention consists in forming and using abcX-knife, or a series of knives, attached to the lower edge of a box, and of 'a form to correspond with the shape of the slate, and in using, in connection therewith, elastic blocks or cushions, 'as will be hereinafter described. l

Figure 1 represents a side elevation of the machine, showing the frame by which it is supported, and the cutting-block.

Figure 2is a. view of one side of the c`utter-box.

Similar letters of reference indicate corresponding parts. g

A is a platform, or the base of the frame, and B is a cap-piece, occupying a horizontal position parallel with the base, and connected with it by vertical rods at the four corners, which rods are marked C. This frame is rectangular in form, and of suitable height. Near the centre of the platform A stands the cutterblock, marked D, surrounding which are four more upright rods, marked E. These rods E are guides'or ways,- which govern the descent ofthe cutter-box., The cutter-box is marked F, and isshown in section in the drawing. i i A In holding slate to be cut, it requiresyielding surfaces to come in contact with it, otherwise the slate will often be broken. I have found that elliptic or carriage springs a a', arranged as shown in the'dr-awing, answer a good purpose. Attached to these springs, or directly to the lower one a', I have an elastic block, G. This block, as the cutting-box descends, strikes the slate, which lies upon the block D, (represented in re l,) and is thereby forced uprinto the box, allowing the edge of the cutting-box, or the knives, to cut the slate. This box F, or its lower edges, (or sides and ends,) are knives or cutters placedat different angles, with sharp rightangled punches at each` corner, for the purpose of cutting the angles 'of the sla-te and giving a start to the cutters. The upper edges of the cutter-block D form cutters, so that when the Vbox and knives :are .brought down on to the slate the knives surround the block, and the slate is cut over the edges of the block. Within the edge surrounding the cutter-block, or over the surface of-the block, within the cutters, there is an elastic cushion, on to which the pieceof slate is pressed by the elastic block G and the force of the springs above it. Springs may also be usedonthe block D., The cushion within the cutters on the block D must stand a half inch or so abovethe cutters, in order that the slate may receive the descending block and be pressed between the two elastic surfaces before the knives touchfit. The box-knife, aswell as the cutters on the block Dmare made of hardened cast steel. Rubben or any other suitable elastic material may be-used for the block Gr and the cushion on the block D.

By this arrangement I am enabled to cut a piece of slate entire at a single blow or motion, instead of cutting the four sides at different times, as is the usual practice, thereby saving 4much valuable time, besides performing the work in a. much moreperfect and satisfactory manner.

What I claim, and desire to secure by Letters Patent, is

1. The four-sided'box-knife F, the elastic block G, and the cushion within thecutters on the block D, arranged and operating substantially as described, for the purposes set forth.

2. In comhinationwith the'cutter-box knife F, I claim the springs a a, or their equivalents, and also the usc of springs under the cushion of thehblock D, substantially as and for the purpose set forth.

THOMAS R. DRUMMOND. Witnesses:

THOMAS S. Jones, Jouw GsMMrLr.. 

